Differential cross sections in antiproton- and proton-helium collisions

Abstract

Cross sections are presented for the first time for antiproton-helium collisions at an energy of 945 keV differential in longitudinal electron and recoil-ion momenta. The longitudinal momentum distributions for antiproton impact are compared with 1 MeV proton-helium collision. The electron and the recoil-ion momentum distributions for antiprotons agree with those for protons to within 10%. We did not observe a difference between antiproton impact and proton impact. A comparison with CDW and CTMC theories is presented.